The validation of thyroid tumor-related genes reveals that the methylation levels of CHST2, DPP4, DUSP6, ITGA2, SLC1A5, TIAM1, TNIK, and ABTB2 were significantly lower in thyroid cancer patients when compared to the controls, while the methylation levels of GALNTL6, HTR7, SPOCD1, CDH16 and GRM5 were significantly higher (Supplementary Table S5, Figure S8). Here, DPP4 is linked to thyroid cancer.